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The table below shows data from a study comparing what people said their annual income was (in thousands of dollars), as opposed to what they reported on their tax return. Assuming alpha=0.10, use this data to test the claim that people say they have a greater annual income than what they actually report on their taxes. Said 140 123 100 84 75 71 for Tax 139 118 99 84 72 70 What is the mean of the difference in incomes (d-bar)? [dbar] (round to 1 decimal)What is the standard deviation of the difference (s-d)? [sd] (round to 2 decimals)What is the left critical value? [cvL] (round to 2 decimals – enter “na” if there is none)What is the right critical value? [cvR] (round to 2 decimals – enter “na” if there is none)What is the value of the test statistic? [ts] (round to 2 decimals)What is the result of the hypothesis test? [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

Market researchers studying the demographics of soda drinkers claim that the average age of Coke drinkers is greater than the average age of Mountain Dew drinkers.To test their claim, the researchers randomly select 300 Coke drinkers and 300 Mountain Dew drinkers. The average age of the Coke drinkers is 35.2 with a standard deviation of 15.22 years, and the average age of Mountain Dew drinkers is 29.7 with a standard deviation of 15.88 years.Based on this data, and using an alpha=0.05, answer the following questions and test the claim.The left critical value = [left] (round to 2 decimals – if there is no left value, enter “na”)The right critical value = [right] (round to 2 decimals – if there is no right value, enter “na”)The test statistic = [ts] (round to 2 decimals)The result of the hypothesis test is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

In a study of in-person vs. online statistics courses, a researcher wishes to test the claim that the average student grade in in-person stats courses is higher than the average student grade in online stats courses. To test this claim 70 in-person student’s grades are randomly selected, with an average of 87.2 and a standard deviation of 4.14. In addition, 60 online student’s grades are randomly selected, with an average of 86.0 and a standard deviation of 3.81. Based on this data, and using an alpha=0.05, answer the following questions.The left critical value = [left] (round to 2 decimals – if there is no left value, enter “na”)The right critical value = [right] (round to 2 decimals – if there is no right value, enter “na”)The test statistic = [ts] (round to 2 decimals)The result of the hypothesis test is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

In a study of in-person vs. online statistics courses, a researcher wishes to test the claim that the average student grade in in-person stats courses is at least as high as the average student grade in online stats courses. To test this claim 70 in-person student’s grades are randomly selected, with an average of 83.7 and a standard deviation of 7.98. In addition, 60 online student’s grades are randomly selected, with an average of 85.0 and a standard deviation of 8.83. Based on this data, and using an alpha=0.20, answer the following questions.The left critical value = [left] (round to 2 decimals – if there is no left value, enter “na”)The right critical value = [right] (round to 2 decimals – if there is no right value, enter “na”)The test statistic = [ts] (round to 2 decimals)The result of the hypothesis test is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

Various studies are conducted to compare the rates of addiction to prescription drugs across various populations. One such study compares the proportion of Utah vs Arizona residents who are addicted to prescription drugs. Data is collected from 1600 randomly selected Utah residents, and shows that 123 are addicted to prescription drugs. Data collected from 1900 randomly selected Arizona residents indicates that 132 are addicted to prescription drugs. Use this data, assuming alpha=0.10, to answer the following questions and test the claim that the proportion of Utah residents addicted to prescription drugs is different than the proportion of Arizona residents who are addicted to prescription drugs.The value of p-bar (pooled p) = [pbar] (round to 3 decimals)The left critical value = [left] (round to 2 decimals – if there is no left value, enter “na”)The right critical value = [right] (round to 2 decimals – if there is no right value, enter “na”)The test statistic = [ts] (round to 2 decimals)What is the result of the hypothesis test? [result] (enter “reject H0” or “fail to reject H0”)

A weight loss product claims that, after a week of using their product, a person’s weight will go down by more 5 pounds. To test this claim, 5 people are randomly selected who use the weight loss product for a week. Before and after weights are  shown in the table below. Use this data to answer the following questions and to test the claim. Assume alpha=0.01. Before 155 189 142 245 288 After 150 183 137 239 282 What is the mean of the difference in weight (d-bar)? [dbar] (round to 1 decimal)What is the standard deviation of the difference in weight (s-d)? [sd] (round to 2 decimals)What is the left critical value? [cvL] (round to 2 decimals – enter “na” if there is none)What is the right critical value? [cvR] (round to 2 decimals – enter “na” if there is none)What is the value of the test statistic? [ts] (round to 2 decimals)What is the result of the hypothesis test? [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

Market researchers studying the demographics of soda drinkers claim that the average age of Mountain Dew drinkers is not the same as the average age of Coke drinkers.To test their claim, the researchers randomly select 300 Mountain Dew drinkers and 300 Coke drinkers. The average age of the Mountain Dew drinkers is 29.4 with a standard deviation of 10.65 years, and the average age of Coke drinkers is 27.6 with a standard deviation of 9.79 years.Based on this data, and using an alpha=0.10, answer the following questions and test the claim. The left critical value = [left] (round to 2 decimals – if there is no left value, enter “na”)The right critical value = [right] (round to 2 decimals – if there is no right value, enter “na”)The test statistic = [ts] (round to 2 decimals)The result of the hypothesis test is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

A weight loss product claims that, after a week of using their product, a person’s weight will go down by more 4 pounds. To test this claim, 5 people are randomly selected who use the weight loss product for a week. Before and after weights are  shown in the table below. Use this data to answer the following questions and to test the claim. Assume alpha=0.05. Before 155 189 142 245 288 After 150 183 137 239 282 What is the mean of the difference in weight (d-bar)? [dbar] (round to 1 decimal)What is the standard deviation of the difference in weight (s-d)? [sd] (round to 2 decimals)What is the left critical value? [cvL] (round to 2 decimals – enter “na” if there is none)What is the right critical value? [cvR] (round to 2 decimals – enter “na” if there is none)What is the value of the test statistic? [ts] (round to 2 decimals)What is the result of the hypothesis test? [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

A random sampling of n=22 Jeep owners showed an average spend on aftermarket accessories of $2750, with a standard deviation of $650. Using an alpha of 0.02, answer the following questions related to a claim that the average amount Jeep owners spend on aftermarket accessories is more than $2,500. H0: mu [c1] $2500 (enter correct sign(s))H1: mu [c2] $2500 (enter correct sign(s))The claim is an [m1] (enter H0 or H1)The critical value on the left, if there is one = [cv1] (round to 3 decimals-if none, enter “na”)The critical value on the right, if there is one = [cv2] (round to 3 decimals-if none, enter “na”)The test statistic = [ts] (round to 3 decimals)The result of the hypothesis test of H0 is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter yes or no)

A claim is made that the proportion of kids who play sports is at least 33%. A sample of n=250 subjects is randomly selected, and data shows 28% play a sport. Assume an alpha of 0.01, and answer the following questions:H0: p [c1] 33% (enter correct sign(s))H1: p [c2] 33% (enter correct sign(s))The claim is [m1] (enter H0 or H1)The critical value on the left, if there is one = [cv1] (round to 3 decimals-if none, enter “na”)The critical value on the right, if there is one = [cv2] (round to 3 decimals-if none, enter “na”)The test statistic = [ts] (round to 3 decimals)The result of the hypothesis test of H0 is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter yes or no)